As the world's smallest cephalopod, the Japanese pygmy squid is easy to keep, making it an excellent animal for the behavioral experiment in the laboratory. Taking full advantage of this feature, we have conducted various studies on the species, from basic information on reproductive biology to its unique mating behavior. In particular, we found that females of this species selectively store sperm ejaculated from a certain male by removing the sperm mass delivered by the male before it is transferred to the sperm storage organ. In this article, we outline the process by which this unusual mate choice was discovered and discuss the evolutionary background of this process.
展开▼
